Modern aerospace technologies have placed increasing demands on polymer technology. Polymeric materials used in this environment should exhibit a variety of physical properties such as low temperature processability, strength, moisture resistance and solvent resistance. Although polymeric compounds exist that exhibit one or more of the above physical properties, these materials generally do not have the desired combination necessary for many applications.
For instance, the popular commercial epoxies provide good strength as adhesives yet they are very susceptible to moisture which causes swelling. Swelling results in dimensional changes which may cause application problems where tight tolerances are required. In addition, swelling results in the loss of mechanical properties such as strength. Another class of polymers, polysulfones, exhibit good thermoplastic processing characteristics and good strength yet they are not very resistant to many solvents including moisture. By contrast polyimides generally exhibit poor processability by typical thermoplastic techniques but provide good resistance against a number of solvents. However, even polyimides generally absorb moisture resulting in swelling and loss of mechanical properties.
Accordingly, there is a continual search in the art for polymeric compounds exhibiting improved physical properties.